[Ktechlab-devel] Simulating an amplifier.

[Dan Andersson]

Alan,

First, I assume you run Linux, if not - eeek! good luck.

You most probably need a more "complete" or "extensive" simulator than 
ktechlab for this! No offense to ktechlab but use Spice3 or NGSpice.

Look for the simulators where you can define tapped mutual inductors.


Dan / M0DFI

On Wednesday 14 June 2006 01:43, Alan Grimes wrote:
> Hello, I'd like to simulate an amplifier before buying many many
> expen$ive components.
>
> Naturally such a simulation will need to take into account many of the
> parasitic properties of the components such as grid-plate capacitance,
> or, for capacitors, ESR and ESL.
>
> I'm going to need a transformer component too, actually the ability to
> specify arbitrary transformers...
>
> As an initial experament, I was trying to hack together a rectifier and
> came across these problems:
>
> 1. To try to simulate a center tapped transformer, I tried to use a pair
> of voltage sources, that didn't work because there was no way to specify
> that the outputs on the two ends should be precisely out of phase.
>
> 2. I now have it running with one generator at 1hz, and I'm looking at
> my rectifyer diode, it is showing both positive and negative voltage
> swings on both sides! Very very wrong.
>
> 3. I put an ammeter and a load in the cirtuit, the left side of the
> ammeter is showing the correct voltage, however the right hand side is
> still pretending as if I still had the thing set at 60 hz!!! =(
>
> 4. I want to snub the rectifier with a 0.1 ufd capacitor but the sim
> crashes, as was previously discussed...
>
> The smallest capacitor in the design I'm working on is .33 pf. =P
>
> To model an amplifier, I'm going to need parts for the basic common tube
> types, (triode and pentode). For generality, it'd probably be best to
> allow the user to enter custom values.
>
> Popular triodes include: 300B, 2A3, 45, 71A, 845
> Popular pentodes include: KT88, 6550.
>
> (The tube I'm working with includes both a triode and a pentode, 6GV8 )
>
> I am a skilled programmer so I'd like to contribute as much of the new
> functionality as I can.